Quality Assurance
End-to-End Quality Assurance for Reliable Software Delivery.
At Core, Quality Assurance (QA) isn’t an afterthought, it’s part of how we build. Over the years, we have handled some of the most complex application migrations in North America, and along the way, our approach to QA has evolved into something we are proud to offer on its own. The same deep, hands-on testing methodologies that safeguards our modernization projects powers standalone service to companies that need expert oversight and reliable outcomes.
We work across the full QA spectrum. Our teams design and maintain automated test suites using tools like Playwright to simulate actual user behavior in real browsers. We also build custom scripts to run alongside your application code, making it easier to catch bugs early and release with confidence. If you are doing A/B testing, trying out different layouts, wording, or flows, Core can help design the test, run it, and make sense of the results.
Our process isn’t about chasing perfection. It’s about making sure software works as it should, across edge cases, environments, and platforms. With deep experience in test frameworks like JUnit for Java and NUnit for .NET, we create repeatable tests that slot into your CI/CD pipelines, quietly doing their job behind the scenes. We also bring DevOps thinking into the QA space, using automation to keep pace with fast-moving development.
If you are building something new or refactoring something old, Core’s QA team can give your team the backup it needs. We plug in where you need us, designing tests, writing scripts, running coverage, and helping teams ship software they can stand behind. It’s what we’ve always done for ourselves, and now, we’re doing it for others too.
Using QA and Testing in Legacy Migration and Modern Application Development Projects
Quality Assurance (QA) is a critical pillar of the CORE modernization process. Legacy applications often lack structured automated testing, relying heavily on manual verification, institutional knowledge, and operator-driven workflows. Modernization introduces an opportunity to establish a comprehensive testing strategy that ensures the migrated system behaves consistently with legacy expectations while benefiting from modern tooling, automation, and validation practices.
What Happens to Legacy Testing During the Migration?
Legacy systems rarely include dedicated unit tests, integration tests, or regression suites. Much of the validation is done through user testing, printed reports, or operational experience. During modernization, CORE captures all business rules, workflows, data flows, and outputs in the CORE Repository. This information becomes the foundation for building automated test suites using NUnit for .NET systems, JUnit for Java systems, and front-end testing frameworks for modern UI components. The goal is to validate each modernized component systematically, ensuring functional fidelity to the original system.
How QA Supports Data, Workflows, and Business Logic
As data structures are normalized into relational schemas and business logic is migrated into service layers, QA teams validate that every transformation, calculation, and workflow path behaves correctly. Test cases are derived from legacy outputs, sample datasets, and recovered rules. Automated regression testing compares new results with legacy equivalents to confirm accuracy. Integration tests validate REST API behavior, data access layers, and batch operations. End-to-end tests verify that UI workflows align with original business processes.
How QA Fits Into the Modern Application Architecture
QA operates across all layers of the new application. In the Presentation Layer, React, Angular, or WPF components are subjected to UI and functional tests to ensure they behave as expected. In the Business Logic Layer, service methods are validated through unit and integration tests. Batch operations in Spring Batch or .NET are tested through automated execution scenarios that confirm data flows and business outcomes. QA engineers verify that Red Hat SSO authentication flows function smoothly and integrate correctly with backend applications.
How QA and Testing Support Enterprise Reliability and CI/CD Pipelines
Modern QA is tightly integrated with DevOps practices. Automated test suites run in CI/CD pipelines to catch regressions early, enabling stable and predictable deployments. Testing frameworks provide coverage reporting, performance validation, and detailed error diagnostics. This level of testing sophistication replaces the error-prone manual verification of legacy systems and ensures long-term reliability and maintainability of the modernized application.
Conclusion
QA and Testing are foundational components of a successful modernization project. By combining automated testing, structured test design, and modern validation tools, CORE ensures that migrated systems maintain functional accuracy, reliability, and performance while meeting enterprise quality standards.
Our QA practice goes beyond manual testing. We build reliable, maintainable test suites using Playwright to simulate real user behavior across browsers.
We develop test scripts alongside feature code to ensure quality is embedded from the start. This approach shortens QA cycles and improves confidence with every release.
A/B testing is a way to compare two versions of something — version A and version B — to see which one works better or gives the results you’re expecting. A/B testing used in software, design, and data work to make sure changes actually improve things.
Core has embraced DevOps not just as a toolset — but as a mindset. From CI/CD pipelines to infrastructure automation and environment provisioning, our workflows are designed to move quickly without sacrificing quality or control.
Playwright is a powerful testing tool we rely on to ensure browser-based applications work flawlessly. We use it to write, run, and maintain automated UI tests — saving time and catching bugs early.
JUnit is a widely-used testing framework for Java that helps developers write and run repeatable automated tests. It supports test-driven development and ensures code reliability by making it easy to identify and fix bugs early in the development lifecycle.
NUnit is a popular unit-testing framework for .NET applications, enabling developers to create and execute automated tests with ease. It supports test-driven development, continuous integration, and helps ensure code quality and reliability across C# and other .NET languages.